try
    {
      MemoryStream MStream = (MemoryStream)Session["Stream"];
      try
      {
        HttpContext.Current.Response.Buffer = true;
        HttpContext.Current.Response.ClearContent();
        HttpContext.Current.Response.ClearHeaders();
        HttpContext.Current.Response.ContentType = "application/pdf";
        HttpContext.Current.Response.AddHeader("Content-Disposition", "attachment;filename=dummy.pdf");
        HttpContext.Current.Response.BinaryWrite(MStream.ToArray());

      }
      catch
      {
        HttpContext.Current.Response.ContentType = "text/html";
        HttpContext.Current.Response.Write("Fehler beim Herunterladen der Pdf-Datei");
      }
      finally
      {
        MStream.Flush();
        MStream.Close();
      }
    }
    catch
    {
      HttpContext.Current.Response.ContentType = "text/html";
      HttpContext.Current.Response.Write("Fehler beim Herunterladen der Pdf-Datei");
    }
    finally
    {
      HttpContext.Current.Response.End();
    }